TY - JOUR
T1 - The Influence of Ecosystem and Phylogeny on Tropical Tree Crown Size and Shape
AU - Shenkin, Alexander
AU - Bentley, Lisa Patrick
AU - Oliveras, Imma
AU - Salinas, Norma
AU - Adu-Bredu, Stephen
AU - Marimon-Junior, Ben Hur
AU - Marimon, Beatriz S.
AU - Peprah, Theresa
AU - Choque, Efrain Lopez
AU - Trujillo Rodriguez, Lucio
AU - Clemente Arenas, Edith Rosario
AU - Adonteng, Christian
AU - Seidu, John
AU - Passos, Fabio Barbosa
AU - Reis, Simone Matias
AU - Blonder, Benjamin
AU - Silman, Miles
AU - Enquist, Brian J.
AU - Asner, Gregory P.
AU - Malhi, Yadvinder
N1 - Funding Information:
We thank the Servicio Nacional de Áreas Naturales Protegidas por el Estado (SERNANP) and personnel of Manu and Tambopata National Parks for logistical assistance and permission to work in the protected areas in Peru. We also thank the Explorers’ Inn and the Pontifical Catholic University of Peru, as well as ACCA for use of the Tambopata and Wayqecha Research Stations, respectively. We are indebted to Professor Eric Cosio (Pontifical Catholic University of Peru) for assistance with research permissions and sample storage. Importantly, we are grateful to all fieldworkers (especially tree climbers) who participated in the field campaigns. We are grateful to Stephanie A. Bohlman for advice on study design, and Beisit L. Puma Vilca for manuscript feedback. Tambopata was installed by Oliver Phillips, many recensuses there were supported by RAINFOR, and Rodolfo Vasquez and Abel Monteagudo provided botanical expertise there. Funding. This work was a product of the Global Ecosystems Monitoring (GEM) network (gem.tropicalforests.ox.ac.uk) the Andes Biodiversity and Ecosystems Research Group ABERG (andesresearch.org), the Amazon Forest Inventory Network RAINFOR (www.rainfor.org), and the Carnegie Spectranomics Project (CSP; spectranomics.ciw.edu) research consortia. The field campaign was funded by grants to YM from the UK Natural Environment Research Council (Grant NE/J023418/1), and from a European Research Council Advanced Investigator grant GEM-TRAITS (321131). GA and the Carnegie team were supported by the endowment of the Carnegie Institution for Science and a grant from the National Science Foundation (DEB-1146206). AS and LB were partially supported by John Fell Fellowships from the University of Oxford. IO was supported by a Marie Curie Intra-European Fellowship. BB was supported by a NSF doctoral dissertation improvement grant and a NERC independent research fellowship. BM and BM-J were partially supported by CNPq research productivity grants (Pesquisador PQ), and Brazilian co-authors are grateful to the National Council of Science and Technology of Brazil (CNPq) for financial support for project CNPq / PELD site 15 (Newton Fund/CNPq 441244/2016-5), FAPEMAT project RedeFlor (0589267/2016), CNPq/PPBio project Phytogeography of Amazonia/Cerrado Transition (457602/2012-0), coordinated by BSM and BHM, respectively and CNPq productivity grant PQ1 for BSM and BHM. Inventory work was funded by the Gordon and Betty Moore Foundation and the US National Science Foundation Long-Term Research in Environmental Biology program.
Publisher Copyright:
© Copyright © 2020 Shenkin, Bentley, Oliveras, Salinas, Adu-Bredu, Marimon-Junior, Marimon, Peprah, Choque, Trujillo Rodriguez, Clemente Arenas, Adonteng, Seidu, Passos, Reis, Blonder, Silman, Enquist, Asner and Malhi.
PY - 2020/10/9
Y1 - 2020/10/9
N2 - The sizes and shapes of tree crowns are of fundamental importance in ecology, yet understanding the forces that determine them remains elusive. A cardinal question facing ecologists is the degree to which general and non-specific vs. ecological and context-dependent processes are responsible for shaping tree crowns. Here, we test this question for the first time across diverse tropical ecosystems. Using trees from 20 plots varying in elevation, precipitation, and ecosystem type across the paleo- and neo-tropics, we test the relationship between crown dimensions and tree size. By analyzing these scaling relationships across environmental gradients, biogeographic regions, and phylogenetic distance, we extend Metabolic Scaling Theory (MST) predictions to include how local selective pressures shape variation in crown dimensions. Across all sites, we find strong agreement between mean trends and MST predictions for the scaling of crown size and shape, but large variation around the mean. While MST explained approximately half of the observed variation in tree crown dimensions, we find that local, ecosystem, and phylogenetic predictors account for the half of the residual variation. Crown scaling does not change significantly across regions, but does change across ecosystem types, where savanna tree crowns grow more quickly with tree girth than forest tree crowns. Crowns of legumes were wider and more voluminous than those of other taxa. Thus, while MST can accurately describe the central tendency of tree crown size, local ecological conditions and evolutionary history appear to modify the scaling of crown shape. Importantly, our extension of MST incorporating these differences accounts for the mechanisms driving variation in the scaling of crown dimensions across the tropics. We present allometric equations for the prediction of crown dimensions across tropical ecosystems. These results are critical when scaling the function of individual trees to larger spatial scales or incorporating the size and shape of tree crowns in global biogeochemical models.
AB - The sizes and shapes of tree crowns are of fundamental importance in ecology, yet understanding the forces that determine them remains elusive. A cardinal question facing ecologists is the degree to which general and non-specific vs. ecological and context-dependent processes are responsible for shaping tree crowns. Here, we test this question for the first time across diverse tropical ecosystems. Using trees from 20 plots varying in elevation, precipitation, and ecosystem type across the paleo- and neo-tropics, we test the relationship between crown dimensions and tree size. By analyzing these scaling relationships across environmental gradients, biogeographic regions, and phylogenetic distance, we extend Metabolic Scaling Theory (MST) predictions to include how local selective pressures shape variation in crown dimensions. Across all sites, we find strong agreement between mean trends and MST predictions for the scaling of crown size and shape, but large variation around the mean. While MST explained approximately half of the observed variation in tree crown dimensions, we find that local, ecosystem, and phylogenetic predictors account for the half of the residual variation. Crown scaling does not change significantly across regions, but does change across ecosystem types, where savanna tree crowns grow more quickly with tree girth than forest tree crowns. Crowns of legumes were wider and more voluminous than those of other taxa. Thus, while MST can accurately describe the central tendency of tree crown size, local ecological conditions and evolutionary history appear to modify the scaling of crown shape. Importantly, our extension of MST incorporating these differences accounts for the mechanisms driving variation in the scaling of crown dimensions across the tropics. We present allometric equations for the prediction of crown dimensions across tropical ecosystems. These results are critical when scaling the function of individual trees to larger spatial scales or incorporating the size and shape of tree crowns in global biogeochemical models.
KW - Metabolic Scaling Theory
KW - allometry
KW - tree architecture
KW - tree crowns
KW - tropical trees
UR - http://www.scopus.com/inward/record.url?scp=85097441946&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85097441946&partnerID=8YFLogxK
U2 - 10.3389/ffgc.2020.501757
DO - 10.3389/ffgc.2020.501757
M3 - Article
AN - SCOPUS:85097441946
SN - 2624-893X
VL - 3
JO - Frontiers in Forests and Global Change
JF - Frontiers in Forests and Global Change
M1 - 501757
ER -